RF: Update and factor mount table parsing code

Author: effigies

nipype/utils/filemanip.py

@@ -275,49 +275,48 @@ def hash_timestamp(afile):
     return md5hex
 
 
-def _generate_cifs_table():
-    """Construct a reverse-length-ordered list of mount points that
-    fall under a CIFS mount.
+def _parse_mount_table(exit_code, output):
+    """Parses the output of ``mount`` to produce (path, fs_type) pairs
 
-    This precomputation allows efficient checking for whether a given path
-    would be on a CIFS filesystem.
-
-    On systems without a ``mount`` command, or with no CIFS mounts, returns an
-    empty list.
+    Separated from _generate_cifs_table to enable testing logic with real
+    outputs
     """
-    exit_code, output = sp.getstatusoutput("mount")
     # Not POSIX
     if exit_code != 0:
         return []
 
+    # Linux mount example:  sysfs on /sys type sysfs (rw,nosuid,nodev,noexec)
+    #                          <PATH>^^^^      ^^^^^<FSTYPE>
+    # OSX mount example:    /dev/disk2 on / (hfs, local, journaled)
+    #                               <PATH>^  ^^^<FSTYPE>
+    pattern = re.compile(r'.*? on (/.*?) (?:type |\()([^\s,]+)(?:, |\)| )')
+
     # (path, fstype) tuples, sorted by path length (longest first)
-    mount_info = sorted(
-        (line.split()[2:5:2] for line in output.splitlines()),
-        key=lambda x: len(x[0]),
-        reverse=True)
-
-    # find which mount points are CIFS
-    # init to empty list
-    cifs_paths = []
-        
-    try:    
-        for  path_and_fstype in mount_info:
-            # need to check for tables that have only path and no fstype
-            if len(path_and_fstype) == 2:
-                # if this entry is cifs, add it to list
-                if path_and_fstype[1] == 'cifs':
-                    cifs_paths.append(path_and_fstype[0])           
-            else:
-                fmlogger.debug('mount file system types not described by fstype')
-    except:
-        fmlogger.debug('mount file system type check for CIFS error')
-        return []
+    mount_info = sorted((pattern.match(l).groups() for l in output.splitlines()),
+                        key=lambda x: len(x[0]), reverse=True)
+    cifs_paths = [path for path, fstype in mount_info
+                  if fstype.lower() == 'cifs']
+
     return [
         mount for mount in mount_info
         if any(mount[0].startswith(path) for path in cifs_paths)
     ]
 
 
+def _generate_cifs_table():
+    """Construct a reverse-length-ordered list of mount points that
+    fall under a CIFS mount.
+
+    This precomputation allows efficient checking for whether a given path
+    would be on a CIFS filesystem.
+
+    On systems without a ``mount`` command, or with no CIFS mounts, returns an
+    empty list.
+    """
+    exit_code, output = sp.getstatusoutput("mount")
+    return _parse_mount_table(exit_code, output)
+
+
 _cifs_table = _generate_cifs_table()